<option value="">&nbsp;</option>
<?php 
    
    foreach ($turmaList->getResult() as $value) {
        
        if($value->getTurmaCod() != $turmaTmp){
            
            echo '<option value="'.$value->getTurmaCod().'" >'.$value->getTurmaCod().'</option>';
            
        } 
        
        $turmaTmp = $value->getTurmaCod();
 }
 ?>

